This invention relates to the field of flexible packaging and more particularly to a bundle of block-sealed, side-gussetted bags, each bag having an aperature formed in one side thereof and to the method of forming such bags.
In flexible packaging there are different types of bags formed. There are side weld bags formed by joining ribbon-like films together and sealing the seams. There are bottom weld bags formed by extruding a tubular film and forming a seam along the bottom of the bag. In bottom weld bags the film in flat two-ply form is sealed along one line at a first location to form the bottom of one bag; and perforated or cut along a second line parallel to the first line, to form the top of the next bag.
These bags whether formed as bottom-weld, side-gussetted bags or side-weld bags, are for some uses stacked and block sealed. Anywhere from twenty-five (25) to fifty (50) bags may be stacked and sealed at the same time or the bags may be stacked and sealed sequentially to form a bundle of block sealed bags. That is, the bags are sealed one to the other along an edge, usually the upper edge. Below this sealed upper edge are the perforated lines which allows an individual bag to be removed from the bundle. Generally the seal will be from a fraction of an inch to an inch or more in width. One or more holes may be punched through the block seal in order that the bags may be carried by a dispenser.
When a bag is removed from a block it has a tendency to cling to the bag it contacts such that the removal of one bag from another is hindered. In some uses of such bags, such as in deli counters, checkout registers etc. there is time wasted in separating the bags and subsequently opening the bags which results in frustration and on occasion the bags are discarded because they do not open easily.
It is believed the closest prior art in this field is that cited in my U.S. Pat. No. 4,559,199 which patent is incorporated by reference in its entirety into this disclosure and my copending application Ser. No. 879,899 filed June 30, 1986.
If such bags could be formed with an opening on one side of the bag only, then the problems attendant to opening and then removing such bags from the bundle would be overcome. For example if a crescent shaped opening were formed in one side at the top of each bag, then simply by passing a finger through the opening, grabbing a side and pulling outwardly, a user of the bags would necessarily apply tension to the bag and it would separate from the other bags to which it is joined at the perforated line as well as separate one side of the bag from the other; i.e. open the bag. There are presently available block-sealed, side-weld bags where one side of the bag is shorter than the other. This shorter side generally faces outwardly and the upper edge may be grasped whereby the bag may be removed from the block. Typically this upper edge is formed as a lip. It would be desirable if a side-gussetted bag had this feature, that is, an opening on one side of the bag only, it being well understood that side-gussetted bags pack more easily and are more voluminous than a corresponding dimensioned side-weld bag.
The present invention is in one aspect an improvement of the method of making the side-gussetted, bottom-weld bags such as described in my aforementioned patent or side-gussetted angular gussett bottom-seal bags (square bottom). One side of each of said bags has an opening formed therein. The use of the term "opening" as used in this disclosure is intended to mean an opening in one ply of the bag such as a circle, square, ellipse or the like formed below the upper edge of the side, or that the opening intersects the upper edge of one side of the bag and/or the opening extends from one side to the other side of the bag.
My invention, in another aspect, embodies the block-sealed, side-gussetted bags of my aforementioned application with square bottoms.